how many days in a row can I use endurox?

I try to use it every day, even if I don't work out. Those are also the directors from the company. I'll reiterate that I no longer have "bad days" or "off days" when I run, even after a lay off. I've been taking Endurox for over two years, and even though I went through a plateau phase about the one year mark, i got over the hump and It still helps me with distance running.

Are there any banned s

I'm assuming you ment to write "are there any banned substances in this product". None that are illegal. However, if you are participating competitively, I would ask whatever organization you fall under if using Endurox would be within their parameters. Exc; Deer antler velvet is not illegal, but major sports organizations don't allow it's use.

I ordered this Feb 202) and it was expiring at the end of the month. Are these still close to expiring date?

The expiration date on the outside of the box is correct, your box expires February 2021 (next year).

‭valid until the year?

Yes, it was only recently that I started to have mediocre day (Maybe the last two months). Still could complete the workout, but felt like I wasn't preforming at optimum level. So I got off of Endurox to reset, I went on a run two days ago and was WAY OFF! Had not done that poorly and almost a year. My local GNC isn't carrying it anymore, so now I have to wait for it to arrive in the mail. The stuff really works, give it a try!